【摘要】 从逐次逼近A/D转换器(SA-A/D)的工作原理出发,分别对其核心模块D/A转换器和比较器进行了讨论。SA-A/D转换器中的D/A转换器可分为电压定标、电流定标和电荷定标三种,重点分析了三种目前应用较多的并行电容、分段电容和RC混合结构。SA-A/D转换器中的比较器可分为运放结构比较器和锁存(latch)比较器,实际常常使用这两种结构级联的高速高精度比较器,并配合失调校准技术,达到较高精度。最后,简要总结了SA-A/D转换器的研究现状,阐述了其在精度、速度和功耗三个方面的发展状况。更多还原

【Abstract】 Successive approximation analog-to-digital converters(SA-A/D)are widely used,due to their comprehensive advantages in accuracy,speed,power and cost.Starting with the basic operational principle of SA-A/D converters,digital-to-analog converters and comparators,which are core modules in SA-A/D converter are discussed.Binary weighted capacitor array,segmented capacitor array and resistor-capacitor mixed type,which are three popular architectures,for D/A converters are analyzed in particular.Comparators in SA-A/D converter are also dealt with.Finally,current development of SA-A/D converters are summarized,and progress in resolution,speed and power are described.更多还原